@misc{indiciaeebfd3389f5dd,
  title = {Combined exercise echocardiography.},
  author = {S N Berberich and J R Zager},
  year = {1981},
  doi = {10.1378/chest.80.3.336},
  url = {https://pubmed.ncbi.nlm.nih.gov/7273889/},
  note = {Source identifier: 7273889}
}